Forze VII

Innovating a new era

Continuing and innovating on the base which was set with the Forze VI, the team developed a complete new race car with the ultimate goal of winning in an official race! In August 2017 the Forze VII made the world debut of hydrogen electric racing. Never before had a hydrogen electric car competed in an official race. Forze competed in the Supercar Challenge at the Gamma Racing Day. By competing with gasoline powered cars Forze proved that this technology is feasible, reliable and very exciting.

The Forze VII is built around a LeMans Prototype (LMP) monocoque. LMP cars are the fastest endurance race cars. Therefore the monocoque will not only be the foundation of this car, but also the basis as Forze looks to the future. This allows the team to develop even better race cars and keep setting records!

The Forze VII is build to compete against gasoline powered cars in the Supercar Challenge. By competing in the race at the Gamma Racing Days 2017 the Forze VII became the first hydrogen electric race car, which has ever competed in an official race against gasoline powered cars.

This competition has multiple divisions. The Forze VII debuted in one of the lower classes. This gives the team the opportunity to keep improving the performance and keep developing fuel cell technology to an even higher level.

The Supercar Challenge has a 45 minute race and a 60 minute race. Therefore the race cars require some endurance performance as well. Endurance is one of the advantages of fuel cell technology. By competing in this race the team can fully utilize the qualities of fuel cell technology!

When Forze reaches the fastest division of the Supercar Challenge it plans to move towards endurance racing.

On the 7th of August 2017 the Forze VII became world’s first hydrogen electric race car to compete in a race. It raced against fossil fueled cars in the Supercar Challenge. By setting a third laptime, the potential of hydrogen technology was proven. For this achievement Forze was awarded with the Garage 56 trophy of the Supercar Challenge and the 3rd place of the D:DREAM Innovation Award.

The Forze VII lapped the circuit of Zandvoort in 1:56.76 and the TT Circuit of Assen in 1:57.288.

The complete car is designed by Forze to race against gasoline powered cars. While the car still has a gas pedal, brake and steering wheel, driving it is completely different. Having an energy buffer, which has to be charged at the right time, makes the complete driving cycle different. Luckily, the team has some experienced drivers, which also know all the ins and outs of the system. Together with the engineers they strive for the best lap times.

The aerodynamic bodywork is portrayed in the spinning clip. These components will bend and guide air around the car. This will create downforce.

Although creating downforce, these components are also designed to have a low aerodynamic drag. This combination will ensure we can drive the fastest lap times during our race.

The chassis clearly exists of two different parts. First of all the carbon fibre monocoque, which is an Adess LMP3 monocoque. This will ensure safety for our driver, because this series of monocoque is FIA certified crash tested.

At the rear, the subframe can be clearly seen. Contemporary LMP cars do not have such a structural frame, because they have an engine and gearbox, which give structural support. Because of this, our team members designed a subframe. The Adess monocoque allows a lot of freedom in the design of the subframe. The chassis is completely simulated with finite element method (FEM) analysis to have the best structural performance under the high dynamic loads associated with racecar performance.

In addition to being a complex mechanical machine, the Forze VII carries 3 main sensor systems, which together monitor and regulate the vehicle. The embedded systems are not only the brains and nerves of the car, but also supply all components with the needed low voltage power.

First the nodes, of which there are 8, forming the brains of the vehicle. Each one controls the actuators and reads the sensors of a specific system in the car. Combined the nodes read 520 sensors in 218 devices.

Secondly, the Power Distribution Unit (PDU) converts and distributes the fuel cell power to suitable power for the different devices and nodes.

Lastly, the wiring harness connects the PDU, nodes, sensors and actuators together. Forming a very complex custom system, this is what a special car like the Forze VII needs to race!

A fuel cell stack converts hydrogen and oxygen into water and electricity. The components which supply the hydrogen and oxygen as well as the system which handles the electricity are called the Balance of Plant (BOP). The BOP is designed in-house by Forze.

The hydrogen is stored in two tanks of 350 bar. The hydrogen flow is controlled with a custom valve system. To provide the necessary oxygen for use in the fuel cell, surrounding air is sucked in via an electrically driven air compressor, and aerodynamic effects caused by the body of the car. This system is capable of pumping up to 5000 liters of air per minute. The BOP can produce 100 kW of power.

Although a fuel cell system is relatively efficient with respect to an internal combustion engine, the various subsystems of the car, especially the brakes and motors still need cooling. Therefore, cooling was one of the main design challenges of this car. With the help of simulation tools, the best pump and radiator requirements were obtained. For example one of the pumps can pump 100 liters of water per minute!

Radiators, pumps, and passive aerodynamic effects are used to keep the temperature of the car regulated.

The powertrain has 2 main systems. The first one is the energy storage system, or accumulator. Its function is to keep the fuel cell putting out maximum power continuously through the race and storing it, when no power is needed on the wheels, for example while braking. During the deceleration it also stores the regenerative braking energy, thus utilizing every watt of power.

The Battery Management System manages the energy level of the accumulator and controlling the amount of power that the second system can use: the motorcontrollers. The motorcontrollers, as the name suggests, control the motors. This control is basically converting the voltage of the accumulator to the needed voltage on the motors.

During acceleration the accumulator can release a combined power of 200 kW to the motorcontrollers!

The drivetrain consists out of a few parts. The most important parts are of course the electric motors. Two Yasa P400’s give the car a peak power of 320 kW. This power will be transferred through a gearbox, which is designed and integrated by one of our team members. This gearbox has a gear ratio of 1:4.6, weighing only 6 kilograms!

This design of the drivetrain will accelerate the car from 0-100 km/h in under 4 seconds.

The suspension is the connection between the track, wheels and the rest of the car. It not only has to counter the loads of bumps and corners, but also absorb the impact of these loads.

The suspension consists of 5 main subsystems: the wheel, rim and brakes; hubs; uprights; and A-arms, push-rods and dampers. The wheel hub is one of the parts that makes the bearing connection between the rotating wheel and the A-arms. The upright is the other part of the bearing connection. The A-arms transfer all the horizontal forces to the car and the push-rod is the connection between the upright and the damper, which transfers the vertical loads.

The complete suspension has to be designed well. Countering the loads, while still minimizing the weight without compromising on safety is a key challenge. A good suspension will fully utilize the power of the fuel cell and give the best lap times!

About Forze

Dreamteam Forze was called to life in 2007 to bring a positive contribution to the sustainability of the mobility industry. With 50 passionate and talented students from Delft University of Technology, Forze built the first hydrogen electric race car in the world. The goal of this dreamteam is to promote the use of hydrogen technology in racing. During the eleven years that Forze exists, they have built eight cars and achieved multiple great things with these cars like building the fastest hydrogen race car ever.